Before attempting to measure intervention costs, one must first determine a study's perspective, the types of costs to include/exclude (e.g.,fixed vs. operating, direct vs. indirect), and how to treat costs for training and development. For this study, the provider perspective was used in measuring intervention costs, because a basic assumption was that the intervention would be implemented as incremental changes to an ongoing clinical practice or telephone quit line and not require additional capacity. Therefore, the provider would incur the incremental costs to their practice or pay for an existing intervention. Consequently, in determining intervention costs, development costs (which are “sunk” or nonrecoverable) and research/evaluation costs were not included. Neither were direct costs (e.g., travel costs) nor indirect costs (e.g., lost time at work) incurred by the patient due to participation and not accrued to the provider. Finally, costs for the use of facilities were excluded. Thus, the key cost categories were: (1) personnel (or labor),
(2) materials and supplies, (3) incentives paid to participants, (4) use of equipment, and (5) initial training. Cost data were collected from August 2002 to September 2003.
To calculate personnel costs, we used a time-motion study to determine time spent implementing the 5 A's in each setting. After making several timed observations in each setting to estimate the average time to complete the intervention, we calculated total labor costs by multiplying the mean times recorded by the reported hourly wage and fringe benefit rate paid, based on the skill level of the participating personnel. Personnel costs varied from one setting to another as well as within settings. For example, in the MCO, average wages ranged from $9 per hour plus fringe benefits for a trained counselor to $130 per hour for a physician in a provider's office. To determine personnel costs per pregnant smoker, data were compiled on the number of counseling sessions each woman received, which varied by setting and how early in the pregnancy the participant presented to the provider.
We also calculated costs of materials, supplies, participant incentives, and use of equipment within each setting. These included $5 gift certificates for women who completed the intervention (clinical trial), videos mailed to pregnant smokers (quit line), stickers (MCO), and pregnancy-specific self-help materials (all settings). To estimate these costs, we gathered data on the per-unit costs of self-help materials distributed. Because the ultimate intent was to determine intervention costs per pregnant smoker, we also collected data on the average number of materials provided to each participant.
To estimate training costs, we gathered data on the number and type of personnel who gave and who received training along with time spent and salary plus fringe rates. These were direct costs for trainers and measures of “opportunity costs” for those trained. Average costs of instructional materials and supplies were also included. Training expenses varied widely depending on how much time was spent per training session, size of the training class, and number of pregnant women who were subsequently counseled within a given time frame. Time spent training counselors to work the quit line far exceeded the time spent training the MCO physicians, but was compensated by the lower opportunity costs of counselors vs. physicians and the greater capacity of the quit line counselors to counsel more women within a given time frame.